New climate states are emerging in India, with the country entering a novel climate regime owing to climate change factored by local anomalies (SLA), the emergence of non-analogue climates (NCS), and the changing probability of extremes, scientist Arpit Tiwari revealed at the ongoing Anil Agarwal Dialogue 2026 in Nimli, Rajasthan.
Tiwari, project scientist, BIMSTEC Centre for Weather and Climate, National Centre for Medium Range Weather Forecasting (NMCRWF), Noida, shared outcomes of his recent study during a session at the conclave.
He said the aim of the study was to understand how and where the combined forces of temperature and precipitation change are creating unprecedented drought conditions across India’s diverse geographical zones.
New combinations of temperature and rainfall outside historical ranges develop due to combined warming and circulation shifts, leading to unfamiliar climate regimes, according to Tiwari.
The study involved using daily rainfall data, comparing figures from 1951 to 1980 and 1981 to 2020.
The pre-monsoon season between March and May has seen high maximum and minimum temperatures become the dominant driver, Tiwari said. Such temperatures dramatically increase evaporative demand, desiccating soils and vegetation even in the absence of a rainfall deficit.
During the monsoon months from June to September, a deficit in rainfall becomes the primary trigger for onsetting drought conditions.
The post-monsoon months between October and December can face pre-monsoon conditions after the monsoonal winds retreat and high temperatures can prolong and intensify the dry period by extracting moisture from the ground, stressing Rabi crops.
According to Tiwari, Western Disturbance-induced precipitation in northern India during the winter months of January and February may lead to wet conditions.
Heat, said Tiwari, is a new driver of drought and their findings show that though rainfall is a dominant driver, high maximum temperatures are intensifying drought conditions.
Northeast India, the Himalayas, and the Indo-Gangetic Plain (IGP) show significant drying trends. “The impact is associated with the combined effect of declining rainfall and rising maximum temperatures which intensify drought by increasing evaporative demand,” he said.
This applies to minimum temperatures as well. “Even night-time temperatures have a role, showing a drying influence in the IGP and Himalayas, but a slight moistening signal in Peninsular India, highlighting the complex, region-specific impacts,” Tiwari said.
Western and Peninsular India, on the contrary, reflect wetting trends, primarily driven by increasing rainfall and more frequent convective precipitation events.
The trends of drying and wetting means there is an urgent need for region-specific adaptation plans and a shift from national policy to finely tuned region-specific strategies for water management and agriculture.
India’s drought early warning system needs to be upgraded and made multi-dimensional, with integration of forecasts related to temperature, evaporative demand, and “novel climate” indicators, not just rainfall anomalies.
“We urgently need to develop and deploy crop varieties that can withstand “hot droughts”—combined heat and water stress. This must be paired with revising agricultural calendars and promoting water-efficient practices like micro-irrigation,” he added.
Tiwari concluded with urging sustainable water management in drying zones, especially in critically important but drying regions like the IGP and Northeast.
“Policies must prioritise sustainable groundwater management, large-scale water harvesting, and a strong focus on demand-side interventions to reduce water consumption,” he said.
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